Roadways, which are applied on a support structure, for example, on a concrete support structure, are frequently encountered, for example, as bridges. Such concrete support structures can be sealed by bitumen webs. Because of their thermoplastic behavior, however, bitumen webs can be susceptible to temperature fluctuations. Elastic plastic webs, however, have an elastic behavior that is constant over a broad temperature range and thus perform their function as a seal even under extreme temperature conditions. As the uppermost layer, a bitumen-based support layer can be used in road construction. In this connection, the problem is that a good adhesive bond between the support layer and the material of the support structure, for example, concrete, has to be present, which, of course, applies to the adhesion of all intermediate layers. In this connection, for example, the adhesion between the plastic membrane and the bituminous support layer represents a very difficult problem to solve because of the materials involved.
One starting point for solving this problem lies in the use of melted asphalt as an adhesive between the plastic layer and the bituminous support layer. These systems have, however, the disadvantage that first the melted asphalt has to be applied at a higher temperature, and the bituminous support layer can be applied only after cooling, which, on the one hand, lengthens and increases the cost of the construction of the sealing and/or construction process of the roadway because of this additional step. On the other hand, it has been shown that because of the high axle loads of the motor vehicles used on the roadway, such roadways become deformed and within short periods of time cause accidental damage to the coating of the roadway.
WO 2008/095215 discloses the use of a concrete roadway. It discloses a concrete roadway on a concrete support structure with an intervening plastic membrane as well as an adhesive layer between the plastic membrane and the concrete roadway. To ensure the adhesion of the concrete roadway to the adhesive layer, in this connection the scattering of silica sand into the adhesive layer before its hardening is proposed.
To improve the bond between the plastic membrane and the bituminous support layer, AT 413 990 B proposes the use of a polyurethane-based adhesive primer, onto which a loose granulate of synthetic resin is scattered. On the one hand, the scattering of granulate is associated with several problems. During or after the scattering of granulate, for example, onto concrete support structures that are exposed to wind, it can cause, for example, large amounts of granulate to be swept away by the wind, which results in accidental material losses or in uncontrolled adhesive losses. Moreover, it has been shown that such systems under shear stress have a strong tendency toward an adhesive rupture between granulate and asphalt. The occurrence of an adhesive rupture is an indication of deficient adhesion and can lead to delamination or to leaks, for example, after extended exposure to the environment.